DIY radiator replacement when new rad is smaller

[Nemophilist]

We need to change a radiator in one of the bedrooms.

The room is being renovated currently and decorator is booked in for a weeks time.

I can’t get a plumber out in time so planning on doing it myself.

However, the old radiator is wider than the new one we would need to buy.

The radiator pipes coming out of the floor are therefore wider - would the standard practise be to bend/weld extensions onto the pipes?

The current radiator width is 1460mm wide and we need to go for a 988mm wide

[sherman]

First off
Is the new radiator going to be central in the gap or against the left or right piping?

Its a case of 90 degree bend replacing where the current valve is straight bit of pipe and new inline valve.

Depending on floor state you can move the piping under the floor boards to fit the new radiator rather than above ground.

Its better to have a bit of clearence under the pipe as it makes hoovering etc easier if you go with the above ground method.

[Nemophilist]

It’s going to be centralised between the pipes

The pipe work could be adjusted under floorboards but I’m not too sure that’s fit for a diy’er and also will need to do something about the holes in carpet left behind (carpet relatively new)

[21TonyK]

Definitely adjust the pipework under the boards to fit properly. A few mm or even a few cm can be fiddled but not half a metre. Especially if the room is being decorated etc.

You would probably want to at least partially drain down the system to change the rad anyway so its only a case of taking the boards up and a few more joints.

The holes in the carpet soon disappear.

[Smurfsarepeopletoo]

I changed some Rads a while ago, and the new ones were smaller, after having a mare changing the piping in the hallway, I ended up using a flexi pipe in other rooms, from the TRV to the Rad.

https://www.screwfix.com/p/flexible-hose-1-2-x-1-2...

Like this, but the size I needed.

[Fore Left]

Smurfsarepeopletoo said:

I changed some Rads a while ago, and the new ones were smaller, after having a mare changing the piping in the hallway, I ended up using a flexi pipe in other rooms, from the TRV to the Rad.

https://www.screwfix.com/p/flexible-hose-1-2-x-1-2...

Like this, but the size I needed.

[Cow Corner]

Take the time to do it properly. The bodge will look much worse than a couple of holes in the carpet (which you might be able to partially hide, if you have some offcuts).

Also a good chance that people will accidentally knock or stand on the exposed pipework, if it’s left.

[Liamjrhodes]

After recently replacing multiple radiators in my house in my opinion adjusting the width above the floor level will not look right.

The easiest and best option is to buy a radiator in the same size as the current one.
If that is not possible that means the carpet and floor boards need to be lifted and the pipes adjusted under the floor boards

Any option that involves moving the pipes will require the central heating system to be drained prior to this work which adds another complication for a DIYer

[megaphone]

Why are you reducing the size of the rad?

[Trustmeimadoctor]

I hope your going up in from double to triple panel if you reducing the rad width or you might be getting cold in there!

[Nemophilist]

megaphone said:

Why are you reducing the size of the rad?

The original rad seems to be massive compare the the size of the room but only single panel. The room has recently been reduced in size to make way for a new staircase and I thought a smaller double traditional looking radiator would suit the room better. It’s an old 1890’s house.

[Nemophilist]

Maybe I could find a traditional wider rad that would suit the pipework positions

[megaphone]

I'm changing a few rads as I do up some rooms, I'm going bigger where I can and doubles instead of singles. I want to reduce the flow temps of the heating system, bigger rads allow for lower flow temps. Important if/when you fit a heat pump

[SteBrown91]

In our house we had an imperial single thickness radiator which we replaced with a double thickness one which was not as wide. Pipework was in the floor so to move the pipework would leave a carpet hole so plumber bridged the gap with straight chrome pipe. Looks fine to me.

[Nemophilist]

SteBrown91 said:

In our house we had an imperial single thickness radiator which we replaced with a double thickness one which was not as wide. Pipework was in the floor so to move the pipework would leave a carpet hole so plumber bridged the gap with straight chrome pipe. Looks fine to me.

Sounds like a good solution. Do you happen to have a photo?

[Peanut Gallery]

Radiator extension tail (s) ?

https://www.screwfix.com/p/essentials-1-2-bsp-male...

[dhutch]

Fore Left said:

Smurfsarepeopletoo said:

I changed some Rads a while ago, and the new ones were smaller, after having a mare changing the piping in the hallway, I ended up using a flexi pipe in other rooms, from the TRV to the Rad.

https://www.screwfix.com/p/flexible-hose-1-2-x-1-2...

Yeah, dont do this, they will fail within a few years. Previous owner of my last house used them on one rad and i had to change them as the rubber had swelled to the point the rad didtt even get luke warm.

[Mr Pointy]

Nemophilist said:

SteBrown91 said:

In our house we had an imperial single thickness radiator which we replaced with a double thickness one which was not as wide. Pipework was in the floor so to move the pipework would leave a carpet hole so plumber bridged the gap with straight chrome pipe. Looks fine to me.

Sounds like a good solution. Do you happen to have a photo?

Honestly, it's not a good solution to have 250mm of horizontal pipe at each end unless it's behind something so you'll never see it. The chrome extension tails are meant to fill gaps of 75mm or so, not as big as yours would be. Getting the floor up is really the only solution - or finding a longer radiator.

[98elise]

Get a similar sized rad, and extension tails to make up the difference. Anything else for a DIY'er will be a pain in the arse or look like a bodge.

Adjusting the pipes above the floor looks crap, and below the floor is a pain and you'll need new carpet.

[thepritch]

Nemophilist said:

It’s going to be centralised between the pipes

The pipe work could be adjusted under floorboards but I’m not too sure that’s fit for a diy’er and also will need to do something about the holes in carpet left behind (carpet relatively new)

Yes, adjust under floor. It’s going to be more work, but as it’s an old house, I’m assuming it has boards, so relatively easy to pull up and put back neatly. Worth doing.

You said the room was getting smaller because of a stair case being put in. Can you use some of the carpet that’s being discarded from the stair case area, to ‘plug’ the holes that are left from the rads. Depends on the type of carpet but quite do-able.